You can buy the window felts/seals/etc. lots of sellers even rockauto.
But yes BJs offroad caters to just fsj.
Download a real manual for FREE
Haynes or Chilton is a poor choice for a manual.
Test the lock motors with 12v I bet they are working fine and do not need replacement.
The switches/wiring is 99% the culprit.
You can take apart/clean the switches after 40yrs they are nasty inside or toast.
Same with any other electrical gremlins look @ the connection/wires not uncommon for issues and usually easy to resolve any with some work.
Slow windows are also usually poor switch function or wiring also old window seals/felts/etc. cause friction and need to be replaced.
Again 40yr old stuff and most of time in poor condition.